Flame retardant

Abstract

Mixtures comprising compounds of the formula A ¦ C ANGLE NN ¦ PARALLEL A-CC-A ANGLE N wherein A is either NH2 or N=P(NH2)3, provided at least one A is N=P(NH2)3, have been found to be good flame-retardants for material made from cotton or polyester-cotton having about 30 to 70% by weight cotton. Conveniently the material can be treated with an aqueous solution containing a sufficient amount of said mixtures and the material dried to make the material self extinguishing. Then the treated and dried material is cured at a sufficient temperature to bond said compounds to the material. Alternatively and usually preferably the drying and curing can be accomplished as a single operation.

What I claim is: 
     
       1. A mixture comprising compounds of the formula ##EQU2## wherein A is NH 2  or N=P(NH 2 ) 3 , provided at least one A is N=P(NH 2 ) 3 .